There are many devices which transfer torque, or rotational velocity, from one point to another. Chains, belts and similar direct drive means transfer rotational movement from one gear or pulley or similar drive means to a second or subsequent gear or pulley or similar driven means.
In some applications, it is desirable to transfer relatively high torque from one point to another point, or from one device to another device. In such applications, space limitations may be a factor. The relatively high torque to be transferred may preclude the use of torque transfer devices which cannot handle heavy duty loads, while space does not permit the use of large devices. An example of such space limitations are torque transfer devices which are placed within enclosures. Examples of devices which transfer relatively high torque are tools which are used to tighten fasteners by the application of torque. Engines and motors use torque transfer devices both operationally, such as camshaft drives, and as power take off devices, such as chain drives on motorcycles. High torque and limited space is a factor in such devices.
Various wrenches, extensions, ratchets, adapters and power transfer tools and devices are disclosed in the prior art. Similarly, camshafts and similar devices are driven by the application of relatively high torque where space for the application of the drive means is limited. Problems are encountered with such devices where the devices are enclosed in relatively small housings, or are otherwise required to be relatively compact in comparison to the torque to be transferred. Common problems experienced with the devices of the prior art include friction and wear between the housing of the device and the drive means, inadequate strength of the drive means or gears, and inadequate or improper engagement of the drive means and the gears due to space limitations.
An additional problem which is experienced relates to stretching of the drive means. The drive means is subjected to substantial forces as power is transferred from one drive gear to the other drive gear. Over time, the drive means will stretch, causing problems in the operation of the device.
Other drive means jam or bind due to bunching of the drive means at the points of entry or exit to the drive sprockets. The path travelled by the drive means or the structure of the drive means causes such jamming or binding.